The current application relates to downhole drilling. During downhole drilling torque acts on downhole drilling tools which if directed towards drilling instrumentation can lead to their failure. These devices may be very expensive to replace and if damaged could lead to drilling delays and other possible failures.
U.S. Pat. No. 6,447,025 to Smith, which is herein incorporated by reference for all that it contains discloses an oilfield tubular member that includes a pin member and a box member, each have a tapered thread. The pin thread has a root, a crest, a pressure flank, and a stab flank. The box thread has a root, a crest, a pressure flank, and a stab flank. The pin crest has a stab flank pin crest radius and a pressure flank pin crust radius which is at least twice the radius. The improved oilfield connection minimizes damage to the connection during misalignment of the pin member and box member.
U.S. Pat. No. 5,492,375 to Smith, which is herein incorporated by reference for all that it contains discloses a tubular drill pipe having a pin connector at one end and a box connector at the other end has each connector adapted to mate with a connector similar to that at the opposite end of the pipe—but on another pipe, to form a tool joint. The connectors are of the type having two pair of axially abutting make-up faces; a primary annular shoulder formed at the inner end of the base of the pin connector, and an internal secondary shoulder at the inner extremity of the base of the box connector which abuts the end of an outermost nose section of the pin connector.
U.S. Pat. No. 3,651,678 to Zook et al., which is incorporated by reference for all that it contains discloses a through feed thread rolling die for rolling external threads on a cylindrical work piece has an external thread thereon with relieved starting and finishing sections, the starting relief providing flat crests which form a predetermined angle with the roll axis and taper to a diameter at the starting end less than the mean height of the fully formed threads. A modified version tapers the starting section at the larger angle than the predetermined angle of the crests thereby reducing the length of the starting section. The invention includes the method of metal movement caused by the die in the formation of the thread.